The FBI on Monday raided the New York City offices of President Donald Trump’s personal attorney Michael Cohen, seizing evidence related to the payment Cohen made porn star Stormy Daniels on the eve of the 2016 presidential election.

The raid came after federal prosecutors in New York City obtained a search warrant following a referral from special counsel Robert Mueller, Cohen’s lawyer said.

Mueller is investigating Russian interference in the 2016 presidential election and related issues, including possible collusion by officials in the Trump campaign with Russians.

NBC News reported that the raid occurred at a law office at 30 Rockefeller Plaza, located in Midtown Manhattan. Vanity Fair additionally reported that FBI agents also visited a room at the Loews Regency Hotel in Manhattan, where Cohen has been staying and executed the warrants there.